The spate of violent crimes committed by National Football League players in recent years has left commentators groping for explanations. Sports journalist Bob Costas argues that America's prevailing "gun culture" is to blame.

Others have blamed the brutal nature of football. "There's something rotten in the NFL," New York Times columnist Frank Bruni writes, "an obviously dysfunctional culture that ... brings out sad, destructive behavior in its fearsome gladiators."

While the NFL has always been violent, the high level of crime among players reached a crescendo in the 2013 off-season with players arrested or charged at least 37 times, according to USA TODAY's database. The rise in player violence is an indictment not of guns or football itself but of a culture in which most children are raised in broken families. It is a culture that, despite the evidence, many refuse to acknowledge.

According to my analysis of The San Diego Union Tribune's NFL Arrests Database, at least 35 players have been arrested or charged with violent crimes since the beginning of the 2010-11 season.

Childhood history

Of the 26 players whose family histories I could glean from online research, 21 (81%) grew up in homes in which at least one biological parent (in most cases the father) was absent.

This is not a scientific analysis. But it does raise a question: Does the NFL have a broken families problem?

Broken families are a society-wide problem. Using Census data, the Marriage and Religion Research Institute estimates that 45% of American teens grow up in families in which both biological parents are present and have been married since their child's birth. Fewer than 20% black teens grow up in such homes.

"Boys who grow up in fatherless homes are less likely to get the supervision and modeling they need to steer clear of trouble with the law," Brad Wilcox , director of the University of Virginia's National Marriage Project, told me.

A 2004 study published in the Journal of Research on Adolescence found that boys who grow up apart from their father are two to three times more likely to be jailed by the time they turn 30. A British study published this year found that boys 14 and younger whose parents split were twice as likely to be convicted of a violent crime in adulthood.

Correlation, of course, does not imply causation. Though it might be wrong to suggest that broken homes cause violent crime, it would be equally wrong to ignore the impact that a turbulent upbringing can have.

Consider Rolando McClain, All-American and former first-round draft pick. McClain was arrested three times in the past two years, twice for violent crimes. During a 2011 incident, McClain held a gun to a man's head and fired a shot.

McClain grew up with sporadic contact with his father, who pleaded guilty to selling cocaine when his son was 11. As a teen, McClain got a restraining order against his mom after she beat him and threatened to kill him. After that, McClain bounced between homes of family and foster parents. This spring, at 23, McClain retired from professional football to get "my personal life together."

Jones had few male role models growing up. "None of the males on my dad's side ever got to see 25," he once told a reporter. "My dad was shot and robbed. (Uncle) Nick was killed trying to rob somebody. My Uncle Ant was stabbed on a bus."

Finally, there's Aaron Hernandez, a former New England Patriots tight end who in June was charged with first-degree murder and is being investigated in connection with more shooting deaths.

Aaron Hernandez's father died while his son was in high school. The loss marked an abrupt turning point in his life. "It was a rough process, and I didn't know what to do for him," Hernandez's mother said. "He would rebel. ... He wasn't the same kid, the way he spoke to me. The shock of losing his dad, there was so much anger." A downward spiral that possibly led to drug use, gang activity, fighting and a murder charge.

Stable families are not a violent crime panacea. There are NFL players from intact families who commit violent crimes, just as there are players from broken families who never do. Many heroic single parents make successful efforts to raise children.

But nothing can replace a mom and a dad at home. They serve as role models, foster self-control, and make kids less vulnerable to peer pressure.

I will leave it to others to argue over whether football promotes off-the-field violence. But we should be able to agree that when mothers and fathers are missing, children suffer. In turn, so does society and the NFL.